Mixed aryloxy aryl silanes



then distilled at 173-184 C. at 0.1 mm. of mer- Patented Apr. 6, 1954 UNITED STATES PATENT OFFICE MIXED ARYLOXY ARYL SILANES Clarence R. Morgan; Marblehead, and Walter F.

Olds, Boston,-Mass., assignors, by mesne assignments, to Galifornia Research Corporation, SanFranciscmCalifi, a corporation-ofDelaware No Drawing. Application January 3', 1950,

Serial No. 136,649

8 Claims; (Cl. 252-78) 1 2 invention relates to the mixed aryloxy the range 775-790 F.; and has arefractive inaryl silanes. dex of 1.5975.

In the use of liquids as heat transfer media The reaction giving this silane is:

it'is' desirable that the liquids resistdecomposi- C6115 ti-on when subjected to high temperatures and 5 I that such liquids remain liquid at or below room H5013 CPAPOI temperatures, that is; that their melting points ctH be low. The aryl orthosilicates have been prowhich results in the esters posed as liquids meeting these requirements;

However in many uses liquids are desirable that are moreresistant tothermal decomposition at higher temperatures than theseorthosilicates. ,11,v

We have found that the mixed aryloxyaryl II silanes; which to-the best of our knowledge are heretofore-unknown, are extremely resistant to lH5 0- i'O"0kHt high temperatures and remain liquid at t'em-- peratures below room temperature and therefore meet the requirements for the uses listed Cam bove. OHC.H40- i-0 0H40H1 It is therefore an object of our invention to 3 provide novel liquids,- the mixed aryloxy aryl I I I I I I silanes, having exceptional high temperature-v wh ch'esters are present in the mixed silanein characteristics with low melting points which 'Q Q I I make these liquids well suited for uses as heat I If qommerclal 9 3 0113537110 d; whlch transfer media includes meta and para" cresol, is used in place The extreme thermal stability of tetraphenyl of creIsol 1n thIls reactlon that more silane (omelet which is a high melting solid f ho mlxed esters compositions a distilling above 950 F. without decomposition, tamed which We mm to have similar high known. Diphenymiphenoxy mane temperature characteristics. These more com- I v a plicated mixed esters compositions may be ('C6H5)2s1('0C6H5)2 identified asmixed-phenyl cresyl esters of di- 1m melting t 7 31 is also known The phenylsila-nedibland includ'ethe following esters mixed arylgxy phenyl-compositionscorrespond. in a transesterified composition Where R is ing to this solid have not beenknown heretofore y R is py R" resyl rad cals. and we have-found that when-aryl esters are c m. 0635 combined with phenyl groups directly' attached 35 g F to silicon, very stable high temperature liquids result which are liquid below room temperatures Cum and which may be generically defined as mixed dic s 05H! aryloxy di-phenyl silanes. 4o

One such novel mixed aryloxy aryl silane we I H have prepared by adding phenol and p-cresol to dichlorodiphenylsilane, a commercially available compound, in equimolecular parts dropwise "0 iOR" Fumes-0R with stirring. When addition of the components H5 EH5 is completed the mixture is heated up to 340 C. over a period of several hours until evolution of It follows that other aromatic hydroxy compounds such as the xylenols and naphthols may HCl is completed. The transesterified product is be used in place of cresol to obtain the aryloxy groups and that the mixed di-aryloxy di-phenyl cury pressure to obtain the mixed phenyl silanes so obtained have similar desirable high cresyl esters of di-phenyl-silane diol. temperature characteristics he mixed Composition of p y D- We have prepared a mixed triaryloxy monoesters of di-phenylsilane diol has been heated phenyl silane by adding to one mole of menufor extended periods at 727 F. without decomphenyl: trichlorosilane, a commercially avail position; has an atmospheric boiling point in able product, dropwise with stirring over a period of from one to two hours a 60-40 per cent mixture of phenol and p-cresol. This mixture was then heated with stirring for 24 hours at 150 C. and at the end of this time very little HCl was evolved. The mixture was then distilled at 185-194 C. at 0.05 mm. of mercury pressure giving a clear liquid having a refractive index of 1.5830 and a pour point of 13 C. (+8 F.) with an atmospheric boiling point in the range 780806 F.

The reaction resulting in this mixed monophenyl triaryloxy silane is:

where R is phenyl and R is p-cresyl. This silane is a mixed ester composition containing the four following difierent phenyl aryloxy silanes: (in en RSiOR R-Si0R' OR OR OR R-s i-OR' OR OR R i-OR on The high temperature characteristics of this silane makes it useful as a high temperature heat transfer medium.

It is now apparent that by the present invention we have provided novel compositions having unusual and desirable high temperature characteristics combined with low melting points which make these liquids ideally suited for the several uses and objects set out above as well as for numerous other uses suggested by their unique physical properties.

It is also apparent that other compositions may now be suggested to those skilled in the art without departing from our inventive concept and reference should therefore be had to the appended claims to determine the scope of our invention.

What is claimed is:

1. A mixture of aryl-triaryloxysilanes obtained by reaction to chemical equilibrium of one mole of aryl-trichlorosilane with a mixture composed of three moles of phenols in equimolecular mole of diphenyldichlorosilane with a mixture composed of two moles of phenols in equimolecular amounts until liberation of hydrogen chloride is essentially complete.

3. A mixture of diphenyl, di-p-cresyl and phenyl p-cresyl esters of diphenylsilanediol obtained by reaction to chemical equilibrium of one mole of diphenyldichlorosilane with a mixture composed of one mole of phenol and one mole of p-cresol until liberation of hydrogen chloride is essentially complete.

4. A mixture of diphenyl, dicresyl and phenyl cresyl esters of diphenylsilanediol obtained by reaction to chemical equilibrium of one mole of diphenyldichlorosilane with a mixture composed of one mole of phenol and one mole of cresol until liberation of hydrogen chloride is essentially complete.

5. A mixture of diphenyl, dixylenyl and phenyl xylenyl esters of diphenylsilanediol obtained by reaction to chemical equilibrium of one mole of diphenyldichlorosilane with a mixture composed of one mole of phenol and one mole oi xylenol until liberation of hydrogen chloride is essentially complete. 6. A mixture of diphenyl, dinaphthyl and phenyl naphthyl esters of diphenylsilanediol obtained by reaction to chemical equilibrium of one mole of diphenyldichlorosilane with a mixture composed of one mole of phenol and one mole of naphthol until liberation of hydrogen chloride is essentially complete.

7. A mixture of phenyl-triaryloxysilanes obtained by reaction to chemical equilibrium of one mole of phenyltrichlorosilane with a mixture composed of three moles of phenols in equimolecular amounts until liberation of hydrogen chloride is essentially complete.

. 8. A mixture of diaryl-diaryloxysilanes obtained by reaction to chemical equilibrium of one mole of diaryl-dichlorosilane with a mixture composed of two moles of phenols in equimolecular amounts until liberation of hydrogen chloride is essentially complete.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,335,012 Johnson Nov. 23, 1943 2,386,793 Hanford Oct. 16, 1945 OTHER REFERENCES Kreshkov et al., Chem. Abstracts, vol. 40, col. 1689 (1946). (Abstracted from Zhur. Khim. Prom. No. 8, pages 10-12 (1944)).

Burkhard et al., Chem. Reviews, Aug. 1947. vol. 41, pages 122, 123. 

1. A MIXTURE OF ARYL-TRIARYLOXYSILANE OBTAINED BY REACTION TO CHEMICAL EQUILIBRIUM OF ONE MOLE OF ARYL-TRICHLOROSILANE WITH A MIXTURE COMPOSED OF THREE MOLES OF PHENOLS IN EQUIMOLECULAR AMOUNTS UNTIL LIBERATION OF HYDROGEN CHLORIDE IS ESSENTIALLY COMPLETE. 